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Properties of 0+ excited states generated by pairing and quadrupole-quadrupole forces in some rare-earth isotopes are investigated. Energies of the 0+ states, probabilities of the E(0) and E(2) transitions, Rasmussen parameters X, and effective cross sections of two-nucleon transfer reactions have been calculated taking into account mixing of the excited states with different Kπ values. The contribution of mixing of the excited states underestimates values of the calculated physical quantities. [ABSTRACT FROM AUTHOR]

To investigate substitution effects on excited-state intermolecular proton transfer (ESPT) reactions as well as acidity of proton donating fragments in the ground state, we synthesized substituted anthracen-2-yl-3-phenylurea derivatives that form a hydrogen bonds with acetate anions and undergo ESPT reaction. Fluorescence lifetime measurements and their kinetic analyses revealed that the trifluoromethyl group on the phenyl ring as an electron-withdrawing group caused a slow ESPT reaction despite an increase in the acidity of the N–H fragment in the ground state. In contrast, the methoxy group as a donating group leads to a fast ESPT reaction despite a reduction of the acidity of the N–H fragment in the ground state. These effects of substituents on ESPT reaction are due to their influence on the charge transfer reaction, which occurs from the N–H fragment to the anthryl ring to increase the acidity of N–H followed by ESPT reaction, over the urea unit by a combination of resonance and inductive effects. These opposing effects of substituents on the acidity of the urea unit in the ground and excited states provide an important insight in balancing the reactivity of proton transfer reaction in both the excited and ground states. [ABSTRACT FROM AUTHOR]